Mr Obama has moved quickly in the last 48 hours to get his cabinet team in place, unveiling a raft of heavyweight appointments, in addition to Hillary Clinton as his Secretary of State.
But his preference for General James Jones, a former NATO commander who backed John McCain, as his National Security Adviser and Arizona Governor Janet Napolitano, a supporter of the war, to run the Homeland Security department has dismayed many of his earliest supporters.
The likelihood that Mr Obama will retain George W Bush's Defense Secretary, Robert Gates, has reinforced the notion that he will not aggressively pursue the radical withdrawal of all combat troops from Iraq over the next 16 months and engagement with rogue states that he has pledged.
Chris Bowers of the influential OpenLeft.com blog complained: "That is, over all, a center-right foreign policy team. I feel incredibly frustrated. Progressives are being entirely left out of Obama's major appointments so far."
Markos Moulitsas, founder of the Daily Kos site, the in-house talking shop for the anti-war Left, warned that Democrats risk sounding "tone deaf" to the views of "the American electorate that voted in overwhelming numbers for change from the discredited Bush policies."
A spokesman for the President-elect was forced to confirm that Mr Obama holds to his previous views. "His position on Iraq has not changed and will not change."
But the growing disillusionment underlines the fine line Mr Obama must walk between appearing to reach out to former opponents and keeping his grassroot supporters happy.
Mr Obama seems conscious of the need to move fast, to reassure a watching world that he will be ready to hit the ground running on foreign and economic policy.
He will wait until Friday before formally announcing his national security team, but he will on Monday formally unveil his economic team, with New York Federal Reserve bank chairman Timothy Geithner as Treasury Secretary and the New Mexico Governor, Bill Richardson, in the Commerce portfolio.
On Friday night, Mr Obama and his wife Michelle revealed that they will send their two daughters Malia and Sasha to the private Sidwell Friends school in Washington, once attended by Chelsea Clinton.
That announcement ended two weeks of speculation in the capital, where excitement is growing over the arrival of the Obama family in time for the inauguration on Jan 20. City officials now expect four million people to turn out to see history made. Hotels are sold out, house rental prices for the week are rising into five figures and others are buying space for their tents on people's lawns. If every visitor descended simultaneously on the National Mall, each would have just one square foot of space.
But the huge enthusiasm of Obama supporters might dissipate if they believe he is crafting a government more likely to pursue "politics as usual", rather than his often-promised "change we need".
There is growing concern among a new generation of anti-war foreign policy analysts in Washington, many of whom stuck their necks out to support Mr Obama early in the White House race, that they will be frozen out of his administration.
Mrs Clinton is expected to appoint her own top team at the State Department, drawn from more conservative thinkers.
A Democratic foreign policy expert told one Washington website: "They were the ones courageous enough to stand up early against Iraq, which is why many supported Obama in the first place." Their fear, he added, is that they will not now secure the mid-level posts which will enable them to reach the top of the Washington career ladder in future.
Suspicion of Mr Obama's moves has been compounded, for some liberals, by the revelation that Mr Obama has for several months been taking advice from Brent Scowcroft, the national security adviser to the first President Bush.
His return to prominence in Washington represents a resurgence of the old school conservative realists, who were largely eclipsed during this Bush administration by the neoconservatives.
They place US national interests above the quest to defend human rights or to spread democracy. Progressives and liberals see Mr Scowcroft's hand in the move to retain Mr Gates, an old friend, at the Pentagon and also in the expected elevation of Gen. Jones.
Others are troubled by an announcement on Friday night that Mr Obama will retain the White House political office, an institution recently associated with George Bush's adviser Karl Rove, who has been blamed for running government as a permanent and highly partisan election campaign.
During the campaign, Mr Obama pledged to end "politics as usual" and the "perpetual campaign".
But a spokesman for the Transition team said: "An Obama White House will be focused on meeting the next challenge, not winning the next election."